This invention relates generally to apparatus for dispensing soluble material into a surrounding body of water. More particularly this invention deals with apparatus that dissolves and dispenses a soluble sanitizing material, preferably calcium hypochlorite, into a body of water, such as a swimming pool utilizing forced circulation.
Chemical feeders, used in previous forced flow or circulation systems, have certain common features. All have typically had a dissolving tank or chamber in which the dissolving of the chemical occurs and a chemical retainer in which the chemical is placed. The dissolving liquid, normally water, is typically fed into the dissolving tank by some control apparatus to ensure the proper amount of chemical dissolved.
Prior equipment, however, normally has suffered from wide fluctuations or variations in the amount of chemical that is dissolved and fed into the water. Most dispensers have utilized a solid chemical that is at least partially immersed in water to effect the dissolution.
Where the chemical is a solid hypochlorite, such as calcium hypochlorite, the solid residue of the chemical has presented either aesthetic or functional problems. When the solid residue has gotten into the forced circulation system, it has resulted in unsightly accumulation on the pool bottom. Build up within the feeder apparatus has resulted in clogging and eventual shutdown of the apparatus. This problem is compounded when larger, commercial pools are treated and larger feeders or dispensers must be used. This clogging also affects the reliability of the feed rate of the chemical into the pools, as well as increasing the frequency of maintenance for these prior feeders.
These problems are solved in the design of the present invention whereby a calcium hypochlorite dispenser operating on the principle of periodic partial immersion with three separate chambers and an improved metering system is provided.